Silencing means for valve structures



No 21, 1944. CORN 2,363,220 I SILENCING MEANS FOR VALVE STRUCTURES Filed July 14, 1943 awe/M0 0 f JossPu Moon Patented Nov. 21, 1944 e i 2,363,220 i i "sILENoiNG MEANS i on vALvE STRUCTURES Joseph Alcorn, Seminole, Okla. i Application July 14, 1943, Serial s dness 3 2 Claims. (Q1. 123-90) This. invention relates generally to improvements in valve structures forinternalcombustion engines, and morespecifically to means for silencvalve-in-head engines. t

The primary object of the invention is to provide simple, inexpensive and practical means for taking upthe lostmotion' and clearancepresent ing the operation ofthe overhead valves used in between the valve rockers and other parts of such valve structures and'holding the rockers in firm contact with the tappetsor pushrods, all to the end of reducing,-or eliminating the tapping noises usually attending the operation of the valves. 1 i 1 Another object is to provide means of this nature which is readily applicable to existing valve rocker mechanisms-without any structural alteration thereof and requiring only slight changes in the meansusually provided forclear- .ance adjustment to compensate forthe addition of my silencing means.- I v With these and other objects in view, the invention resides in the novel construction and arrangement of parts as hereinafter fully set forth and claimed, reference being had to the accompanying drawing wherein Figure l is a side view of a valve rocker mechanism of conventional form, equipped with the silencing means of my invention;

Figure 2 is a top plan view thereof;

Figure 3 is a side, or edge view of the silencing means alone, this view showing only the spring device forming the major part of such means;

Figure 4 is atop plan view of the device of Figure 3;

Figure 5 is a vertical cross sectional view along the line 55 in Figure 1;

Figure 6 is an inverted plan view of the clamp for mounting the spring device of Figure 3 upon the valve rocker.

Referring now more particularly and by reference characters tothe drawing, I have shown my invention as applied to a conventional valve rocker mechanism including a rocker l0 oscillatably mounted on a rocker shaft II and having a valve actuating arm l2 at one end arranged over the end of a valve stem l3. At its other end M, the rocker 10 has a tapped opening IS in which the usual tappet engaging screw I6 is adjustably place the valve stem; Lite Open thevalve (not shown) in usual--mannerr 1 To compensate for the expanslonofthe metal in the valve and stem a clearance must be provided between the rocker arm and valve. stem-so that, as the engine heats, the valve will notbe held open. Theamount of such clearance is adjusted in usual manner by the screw I6 and is locked by the set nut l8 thereon- Such clearance, however, results in lost! motion and a tapping noise during the operation of: the valve mechanism as is well known, and my inventionaims to largely overcome or silence such noises.

i My invention accordingly comprises a spring device, designated generally at l9, includinga main springmember and a secondary spring member 2|, both of which are formed from ini tially flat, leaf spring material. The member 20 has-a flat operating end 22 and a longitudinally extendingfslot 23 which'opens through its other, or mounting,'end24. The slot 23 permits the legs or arms-25; which it forms, of the main spring member to curve upwardly alongside the rocker arm l2, over the hub 26 of the rocker, and to pass alongside the tappet screw l6 beneath the nut l8 thereon, while the operating end 22 of the member is disposed between the end of the rocker arm and the upper end of the valve stem I3, as clearly shown in Figure 1. The arm portion 12 of the rocker is ordinarily narrow (horizontally or parallel with the shaft ll) while the opposite end mounted. This screw. at its lower end engages the tappet or push rod l'l so that the upward movement thereof will oscillate the rocker causing the arm l2 to downwardly engage and dis- I4 of the rocker, ue to its being provided with the opening I5, is

The ends being properly disposed as herein shown, they will bias the rocker to urge the arm l2 and valve stem [3 apart. i

The secondary spring member 2| is herein shown as arranged uppermost to engage the end of the roclrer arm i2 and the end portion of the spring has lateral, upturned lugs 3| (Figure 5) which are clamped over the beads or projections 32 usually found on the lower sides of the arm,

ider and accordingly provides a seat or bearing for the ends of the legs 25 at i to thereby hold both spring members against sidewise displacement relative to the rocker.

The respective operating ends 22 and 21 of the springmembers have contact bosses or points 33 and pressed from their adjacent surfaces and toward each other, the contacting faces of these bosses being centrally concaved as shown at 35 to reduce the effective contacting areas to the narrow annular surfaces 36. l I,

The'mouriting end 24 of the main spring member 20 is engaged by a' rectangular clamp or clamp member 31 which has an opening 38 to pass the screw l6 when the clamp is placed over this end by the positioning of the operating ends of the springs therebetween. This screw IE will, of course, be adjusted to provide the usual slight clearance between the contact bosses 33 and 34 to permit the expansion of the parts due to heat of the engine.

Having now fully disclosed my invention, what I claim as new and desire to secure by Letters P en i v.

1; Ina device of the kindde'scribed for mounting upon a conventionalmedially' pivoted rocker 1 arm of an internal combustion engine, for silencof the spring. The clamp further has depend- I ing lateral flanges 39 which overhang the sides of the spring and said flanges have inwardly projecting teeth 40 which interlock with any opposed pair of a series of notches formed by teeth 4? along both sides of the spring. Thus the: entire spring device may be adjusted lengthwise with respect to the rocker, to bring the contact bosses 33 and 34 properly into-alignment with the axis of the valve stem [3, and with the teeth W and ing the operation of a valve thereof, the said rocker arm being adapted at one end for operating the valve stem of the, valve and at the oppositeend for engaging the conventional tappet by meansof an adjustment screw threadedly passed through that endof the rocker arm, and the said adjustment screw carrying a set nut, anelongated M properly interlocked-and the nut I 3 turned down, suchadiustm'ent will be positively maintained.

It will be apparent that the normally divergent operating ends 22 and 2! of the spring device will yield-ably urgeorbias the rocker arm I2. and valve stem i3 apart so that all lost motion will be eliminated and tapping noises which would arise from such lost motion will be silenced. The

concaved surfaces of the contact bosses 33 and 34 aid in such function by reducing the contact areas involved. and. by a sort of cushioning effect between the contacts due tothe pocketing of air inv such concavitiesas the: contacts close.

The: device as herein disclosed may obviously be applied to the valve without any structural alteration thereof and only the screw lGneed beadjustedto compensate for the added clearance required betweenthe rocker arm and valve stem flat spring provided with divergent branches at one end for positioning between the valvestem and adjacent end of-the rocker-arm for biasing these elements oppositely, the opposite end of said spring including a and longitudinally slotted mounting portion adapted to engage the said adjustment screw beneath the set nut thereof, and means for adjustably securin this end of the spring in place against longitudinal slippage. '2. In a device according toclaim 1, the said means for securing the spring against longitudinal' slippagecomprising ,a flat clamping member centrallyapertured for seating over the adjustment screw beneath the set nut and. against the slotted flat portion of the spring at that end, the

said clamping member having lateral pendant flanges overlapping the margins of the said slotted flat portion of the spring and there being complemental interlocking means on the flanges of the clamping member and contiguous margins of the slotted fiat portion or the spring for locking the elements in any set position. 1

- JOSEPH ALCORN. 

